Oil Pressure Light Flickers

[dhoeschen]

The oil pressure light started to flicker while braking up to a stop light. It would flicker very lightly like an electrical issue. When the RPM came back up again the light would be off.

Another time I was coasting up to a stop sign and the light would flicker and the RPM would come up a little, light would go off. My foot was on the brake not the gas -- what made the RPMs come up?

Could it be low oil? I'm going to try checking the level later today, if I can get the hood open...

[richtazz]

When you're checking the oil, also check to see if it's overfull. This could indicate other problems such as fuel or coolant getting in the oil. Contaminated oil would cause the light to come on due to it being thinned out by these materials.

[BNaylor]

Please post the year and model Grand Prix to include mileage.

[dhoeschen]

Sorry, it's a 1999 Pontiac Grand Prix GTP with about 80,000 miles.

Started up great after work, drove to the gas station to fill it up, no problems.

Got the hood open, checked the oil, it was thin like it was flooded with gasoline but not over full.

Later...the engine died and after re-starting the Check Engine light is on steady and it sounds like it is not firing one cylinder.

Any ideas? Bad fuel injector???

[grandprixgtx00]

does the oil smell like gas? you might have a bad plug or wire. when was the last tune up? i guess go to auto zone and have them pull the code for you...that'll tell ya whats wrong.

[dhoeschen]

Yes, the oil does smell like gasoline.

It hasn't had a tune up, it has been running great. Last time it was at the dealer was in September for the valve cover recall.

I won't be driving it so I'll have to buy or borrow a code scanner.

[grandprixgtx00]

i would prolly just do a tune-up and see what happens, unless you can get access to a scanner. did the SES light ever flicker? thats usually a sign of a misfire.

[dhoeschen]

It was running great after I filled the tank. I was just about ready to put it in gear and the engine died. When I re-started the engine it had the funny clunking dead cylinder sound.

I didn't see the SES flash but it is "on" now. If I fix the issue, will the SES turn off without clearing the DTC with a code scanner?

I'm going to change the oil, pull the plugs and see if I can find a fouled plug. I should be able to trace it back to the coil and then do a resistance check on the coil and plug wire.

How much impedence I should see when checking a coil?
There are 2 plug wires per coil, shouldn't I find 2 dead cylinders?

[BNaylor]

Originally Posted by dhoeschen

How much impedence I should see when checking a coil?
There are 2 plug wires per coil, shouldn't I find 2 dead cylinders?

For stock GM DIS waste spark coils:

Ignition coil primary resistance = 0.5 to 0.9 Ohms
Ignition coil secondary resistance = 5K to 10K Ohms

[dhoeschen]

Thanks for all the help!

Now a bigger problem, I can't get the hood open. I've had trouble with the hood release cable before -- now the release lever snapped off, it's gone...somewhere in the snow, I'll find it in the spring!

Is there a way to release the hood from outside/under the car? What's involved in replacing the hood release cable & new lever?